Actuating mechanism for railway points



1962 w. J. SIMONS ETAL 3,051,421

ACTUATING MECHANISM FOR RAILWAY POINTS 5 Sheets-Sheet 1 amp //A FiledMarch 3, 1961 Aug. 28, 1962 w. J. L. SIMONS ETAL 3,051,421

ACTUATING MECHANISM FOR RAILWAY POINTS Filed March 3, 1961 3Sheets-Sheet 2 1962 w. J. slMoNs ETA].

ACTUATING MECHANISM FOR RAILWAY POINTS 5 Sheets-Sheet 3 Filed March 3,1961 mw ww wv Q Unite States 3,051,425 Patented Aug. 28, 1962 3,051,421ACTUATING MECHANISM FOR RAILWAY POINTS Walford John Louis Simons,Brentford, and Gordon Joseph White, Greenford, England, assignors toRotax Limited, London, England Filed Mar. 3, 1961, Ser. No. 93,095Claims priority, application Great Britain Mar. 4, 1960 2 Claims. (Cl.246401) The object of this invention is to provide actuating mechanismfor railway points in a convenient form including means for locking thepoints in their alternative positions, and means whereby an indicationcan be given at a remote place that the points are set and locked at oneor another of their alternative positions.

Actuating mechanism according to the invention comprises in combinationa first slide adapted for connection to a movable rail of the points, asecond slide movable transversely relative to the first slide, aprojection on one of the slides engaging a slot in the other slide, saidslot having a pair of laterally extending and oppositely directed endportions in which the projection is adapted to be accommodatedrespectively to lock the movable rail in its alternative position, alever pivotally connected to said first slide and operatively engagingthe second slide and actuating means connected to the lever, thearrangement being such that when the projection occupies one of said endportions of the slot, movement of the actuating means in the appropriatedirection will through said lever, first move the second slide todisengage the projection from said one end portion then move to thefirst slide until the projection is opposite the other end portion ofsaid slot, and finally move the second slide to engage the projectionwith said other end portion.

In the accompanying drawings:

FIGURE 1 is a plan view of one example of the invention,

FIGURE 2 is a plan view of another example of the invention,

FIGURE 3 is a plan view of part of FIGURE 2 to an enlarged scale,

FIGURE 4 is a section on the line 4-4 of FIGURE 3, and FIGURE 5 is asection on the line 5-5 of FIG- URE 3.

Referring first to the example illustrated in FIGURE 1 the free ends ofthe pair of switch rails of the points are interconnected by a tie-rod11, and are pivotally connected respectively to a pair of separateslides 12 which form part of a pair of units respectively. The units aresimilar, and are mounted on a common sleeper 13 at the outer sides ofthe pair of fixed rails 14 respectively.

Each unit, in addition to the slide 12 which is movable in guides 15transversely of the fixed rails 14, includes a second slide 16(hereinafter termed the locking plate) which is slidable at right anglesto the slide 12. In the locking plate 16 is formed a slot 17 in which isengaged a roller, pin or other projection 18 extending from the slide12. The main or intermediate part of the slot 17 extends parallel to theslide 12, but at its ends are oppositely directed and laterallyextending end portions which are at right angles to the main orintermediate part, and which are each adapted to accommodate theprojection 18. Moreover, pivotally mounted at 19 on an arm extendinglaterally from the slide 12 is a bellcrank lever 20 having on one of itsarms a roller, pin or other projection 21 which is engaged within asecond slot 22 formed in the locking plate 16, this slot 22 extendingparallel to the main portion of the slot 17.

The other arm of the bellcrank lever is connected by means of a rod orco-axial rods 23 with the complementary arm of the bellcrank lever 20 ofthe other unit, while to an intermediate point of this rod, or theserods 23 is connected a parallel actuating rod 24 movable axially bymanual, fluid actuated, or electrical means 25.

The arrangement is such that when either projection 18 occupies alateral end portion of the slot 17 in the locking plate, the associatedswitch rail 10 is locked in one or other of its alternative operativepositions, and the other switch rail is locked in a similar manner in acomplementary position. If, in this condition, the actuating rod 24 ismoved axially in the appropriate direction, the first eifect will be tomove the two bellcrank levers 2t) angularly in opposite directions,thereby moving the two locking plates 16 in opposite directions to causethe projections to occupy the main portions of the slots 17 (as seen inFIGURE 1). In this position further movement of the locking plates 16 isprevented, so that continued movement of the actuating rod 24 willresult in the slides 12 being moved in the same direction, thus movingthe movable rails 10 to their alternative positions. At these positionsthe projections 18 occupy the opposite ends of their respective slots17, and continued movement of the actuating rod will result in furthermovement of the locking plates 16 until the projections are engaged withthe opposite end portions of the slots, thereby locking the movablerails in their new positions.

In order to give an indication at a remote place of the position of thepoints, each unit incorporates two electric switches, 26, 27, one ofwhich is closed when the associated switch rail 10 is in one operativeposition, and the other of which is closed when the switch rail 10occupies the alternative operative position. The one electric switch ofeach unit is connected in series with the complementary electric switch(i.e. the switch having the same reference numeral) of the other unit ina separate indicator circuit. Also in each indicator circuit and inseries with the aforesaid electric switches is a further electric switch(not shown) closable by the locking plate 16 when the points are in thelocked position. Thus an indication that the points are in eitheroperative position can only be given when both movable rails 10 arelocked in this position.

In the example of this invention illustrated in FIG- URES 2 to 5 onlyone unit is employed, the parts of this unit which are similar to thosein FIGURE 1 being given the same reference numerals with a sufiix. Inthis example the slide 12 is connected to the adjacent movable rail 10which is in turn connected to the other movable rail 10 by a tie-rod 11The slot 17 having the pair of laterally extending and oppositelydirected end portions is formed in the slide 12*, and the projection 18engaging this slot is on the locking plate which is formed as two parts16 16 situated respectively above and below the slide and interconnectedby the projection.

The upper part 16 of the locking plate is situated between the similarparallel and vertically spaced, parts 20 20 constituting the bellcranklever which is pivoted at 19 on the slide 12. Furthermore, the upperpart 16 of the locking plate incorporates a transversely extending slot22 in which is accommodated a pin 21 interconnecting the two parts 20 20of the bellcrank lever adjacent the end of its one arm, this pin 21being surrounded by a square or other rectangular distance piece 30slidable within the slot 22 Slots 31 31 are also formed in the parts 2020 respectively of the bellcrank lever to accommodate movement of theprojection 18 as will now be described.

Assume that the projection 18* is located in the lateral end portion atone end of the slot 17 in the slide and that a force is applied to thearm of the bellcrank lever remote from the pin 21 The first effect ofthis movement will be to cause the bell crank lever to move angu larlyand thereby (through pin 21*) impart movement to the locking plate 16*,16 until the projection 18 is disengaged from the lateral portion of theslot. Further angular movement of the bell" crank lever in the samedirection is now arrested "so that continue'd force in the samedirection will cause the slide12 'to move axially together with the bellcrank lever until the projection 18 is opposite the lateral end portionat the other end of the slot 17 this movement is permitted since the pin21* interconnecting the parts 20 20 of the bell crank lever is movablein the slot 22 in the locking lever. A continued force applied to thebell crank lever in the same direction" will now cause its furtherangular movement so as to move the lockingplate into a position tointroduce the projection 18 -into the other lateral end portion of theslot, and thereby lock the points at the alternative setting.

For imparting the movements to' the bellcrank lever 20, 20 mountedbetween the arms of the two parts remote from the pin 21 is a nut 32engaging screw shaft 33 heldfrom axial movement and rotatable by areversible electric motor34 through reduction gearing 35, and an overload clutch 36.

In this modification the part 16 of the locking plate carries a member37 which is adapted to operate one or other of two banks of electricswitches 38, 39 when the switch rails are locked in one or other of itsalternative positions respectively. Some of each of these banks ofswitches serve to control'the motor 34, others serve to actuate anindicator, for example, in a signal box, whilst others may serve tocontrol a point and signal interlocking circuit.

In addition to the electric switches 38, 39, to each movable tip isconnected one of a pair of rods 40, 41 with each of which is associateda'pair of switches 42, 43 respectively. Each switch 42 is connected in'series with one of the switches 43respectively and with an electricindicator lamp in a signal box, and the arrangement is such that whenbothmovable rail tips are correctly located for one position of thepoint one lamp is illuminated, and when both switch rail tips arecorrectly located in the alternative position the other indicator lampis illuminated.

The slide 12 is connected to the adjacent movable rail through theagencyofa pair of'pins 44 which will be sheared in the event of therelationship between the slide and the rails 10 being upset, as forexample, by a train running through the points with thelatter'incorrectly set. In order to ensure thatno correct indicationwill be given in the signal box after such a'happenin'g even though theslide 12* be again moved into'thecorrect relationship to the rails 10, areadily shearablecondu'ctor 45 is arranged in serieswith the switches42, 43. The'conductor 45 is carried by a pair of relatively slidableparts 46, 47 connected respectively to the slide 12 'and-adjacent'rail10 and has brushes 48 at its ends making contact with con ductor bars49; When the pins 44 are-intact the parts 46,

47 will slide together as the setting of the points is is accompanied bymovement ofthe rail, a second slide movable transversely relative to thefirst slide, one of the slides being provided with a projection, and'theother slide being provided with a slot which is slidablyengaged by theprojection, and'which has a rectilinear main portion parallel with thedirection of movement of the first slide, and'a pair of oppositeend-portions which extendin opposite directions respectively from, andat right angles to, the main portion so that*when the projection is inengagement with-either of the said end portions of the slot the secondslide serves to prevent movement of the first slide, a bell crank leverpivotally mounted on the first slide, and having one end operativelyconnected to the second slide, and actuating means connected tothe-otherend of the lever for imparting movement through the latterto'the first and second slides so that, when the first slide is held ineither of its *extreme positions by the engagement'of the projectionwith one'of the said end portions of the slot, movement of'the actuatingmeans inthe appropriate directionfirst causes the second slide tobemoved through the medium of the lever for effecting disengagement of'the' projection from the lastmentioned end portion'of the slot, thencauses the first slide to be moved through the medium of the lever-t0its other ex-- treme position,:and finally'causes the second slide to bemoved further through the medium of the lever -for effecting engagementof the projection with the other of the'said end portions of 'the slot.

2. Actuating'mechanism according to clai-m'l; and having in combinationelectric switches respectively operable by thesecond slide and themovablerail, an electric*cur-- rent conductor connected in series withthe electric switches, a shearable pin through the medium of which thefirst slide is connectible to the movable rail, and means by which theconductor is supported, and through the medium of which the conductorisshearable at thesame time as the pin, the said means having a pair ofrelatively, movablefparts oneof -which'is connected to the first slide,and the other of which is connectible to the movable rail.

References Cited in the file of this patent UNITED STATES PATENTS l,186,834' Robinson June-l3, 1916 2,082,133 Wyant June" 1, 1937 2,490,742Smith t Dec. 6,"1949 2,740,041 Marcu-m' Mar. 27, 1956 FOREIGN PATENTS16,402/86 Great Bri a n n uenee; 14 1886"

